Abstract: There is provided an oil pressure reduction rate restricting apparatus for a V-belt type continuously variable transmission, which is comprised of a reduction rate restricting section that calculates a reduction rate restricted secondary pressure and a reduction rate restricted primary pressure by restricting respective reduction rates of the target secondary pressure and the target primary pressure when the reduction rates of the target secondary pressure and the target primary pressure calculated by a target secondary pressure calculating section and a target primary pressure calculating section, respectively, are equal to or greater than respective predetermined values. The secondary pressure and the primary pressure are controlled based on the reduction rate restricted secondary pressure and the reduction rate restricted primary pressure whose reduction rates have been restricted such that the gradient thereof are small.

Abstract: There is provided a hydraulic control apparatus for a belt CVT, which is comprised of a pulley pressure control section that controls the line pressure in accordance with the oil amount balance of an oil pump based on the engine speed and the oil temperature during a select-judgment period from the detection of a change from a driving range to a non-driving range or a change from the non-driving range to the driving range to the lapse of a predetermined period of time, or when the non-driving range is detected. This eliminates the possibility that the oil pump cannot generate a specified oil pressure due to a decrease in the engine speed. Further, the secondary pressure is multiplied by the ratio of the line pressure in accordance with the oil amount balance of the oil pump to the line pressure which has been intended to be specified, and the secondary pressure is controlled according to the calculation result. This makes it possible to maintain the pulley ratio without causing a down-shift of the belt CVT.

Abstract: The rigidity of a movable pulley half is enhanced by the rigidity of a cylinder fixed to a back surface of the movable pulley half and influences of a controlled hydraulic pressure and a centrifugal hydraulic pressure which are exerted in a hydraulic fluid chamber partitioned in the cylinder. On the other hand, an annular protruding portion having detection teeth for a rotation sensor is formed on a back surface of an outer circumferential portion of a fixed pulley half, whereby the difference in rigidity between both the pulley halves is reduced by the effect of the annular protruding portion to improve the rigidity of the fixed pulley half, thereby making it possible to allow the variation characteristics of a misalignment relative to a drive ration to approach a characteristic set in advance.

Abstract: CVT control unit of a belt CVT checks whether a reverse rotation of pulleys is generated. When the reverse rotation is generated, a PLpri torque capacity is calculated from a primary pressure Ppri, and this PLpri torque capacity is used as a torque limit value of a torque-down control of an engine control unit. An input torque to a transmission mechanism is compared with the PLpri torque capacity, and when the input torque exceeds the PLpri torque capacity, shortage of the PLpri torque capacity for the input torque is calculated. Then, this shortage is added to the input torque as a correction amount, and a line pressure is set on the basis of a result of this addition.

Abstract: A hydraulic control system for a continuously variable transmission (CVT) includes a ratio control valve for distributing fluid to components in the CVT. The ratio control valve receives a system controlled pressure and distributes both a high pressure control fluid and a low pressure control fluid. A variable bypass valve distributes excess fluid pressure back to the inlet of a control pump. The bypass valve is responsive to the pressure differential between the high pressure control fluid and the system pressure controlled fluid to establish the operating point at which the excess fluid is bypassed. The system pressure controlled fluid is the highest pressure in the system. During operation of the CVT, the high pressure control fluid operates on one variable sheave of the CVT and the low pressure control fluid operates on another variable sheave of the CVT.

Abstract: A continuously variable transmission, having a first pair of conical disks including an axially moveable disk and an axially non-movable disk whereby a running radius of the first pair of disks is changeable, a second pair of conical disks including an axially movable disk and an axially non-movable disk whereby a running radius of the second pair of disks is changeable, and an endless transmission element arranged to couple the first pair of disks with the second pair of disks. A first hydraulic actuator in operative connection with the movable disk of the first pair of disks for axially moving the disk, the first actuator having an inlet port, and a second hydraulic actuator is in operative connection with the movable disk of the second pair of disks for axially moving the disk, the second actuator having an inlet port. A first, four-quadrant controllable pump-motor has a first port connected to the inlet port of the first actuator, and a second port connected to the inlet port of the second actuator.

Abstract: There is provided a line pressure control apparatus that is comprised of a line pressure control section that controls line pressure according to its target value calculated based on input torque information, target gear ratio, and so forth; and a line pressure setting section that sets the upper limit of the line pressure according to an inputted range signal when the engine speed is equal to or higher than a predetermined speed. The line pressure control section suppresses an increase in line pressure by controlling the line pressure such that it does not exceed the set upper limit in the case where the upper limit of the line pressure has been set. Therefore, it is possible to prevent the occurrence of cavitation noise in an oil pump, which generates basic pressure for line pressure, during high-speed engine revolution.

Abstract: In case a primary hydraulic pressure sensor is normal, when reverse rotation of pulleys is detected a primary pulley (Plpri) torque capacity is calculated from a primary pressure detected by the primary hydraulic pressure sensor. When the primary hydraulic pressure sensor fails, a secondary hydraulic pressure sensor is checked, and when the secondary hydraulic pressure sensor is normal, the PLpri torque capacity is determined from a secondary pressure detected by the secondary hydraulic pressure sensor by using a map. On the other hand, when the secondary hydraulic pressure sensor fails too, the PLpri torque capacity is read out from the map by using a secondary pressure target value as the secondary pressure.

Abstract: When an ignition switch is turned off to stop an engine, a control apparatus of a continuously variable transmission places a line pressure regulating valve in a fully draining condition to reduce a load of a hydraulic pump by maintaining an electric power supply to the line pressure regulating valve, a shift control pressure regulating valve and the control apparatus.

Abstract: A method is provided for controlling an output/input speed ratio of a continuously variable transmission (CVT) plant including primary and secondary pulleys actuated by primary and secondary pressures (Pp,Ps,), respectively, which generate forces to move the pulleys and adjust a corresponding belt, thereby adjusting the output/input ratio. The method includes calculating a desired force ratio for the CVT plant. Desired primary and secondary pressures (PP,PS) are then determined based, in part, upon the calculated desired force ratio, and the desired PS and PP signals are sent to the CVT plant to control operation of the CVT plant. An actual speed ratio is calculated based on measurements of input and output speed from the CVT plant.

Abstract: A vehicle transmission, for example a CVT transmission, is provided with a decoupling device between an engine output shaft and a vehicle driveline. The decoupling device in one embodiment includes a clutch assembly which is fixed to a shaft coupled to the transmission output and engageable with a driveline through a piston arrangement. The piston can be urged against the force of a spring by fluid pressure to cause engagement of the clutches of the clutch assembly and thereby to couple engine torque to the vehicle driveline. When fluid pressure is released, the spring urges the piston to a position in which the clutches of the clutch assembly are disengaged, so as to disengage the engine output from the vehicle driveline. In the disengaged state, the vehicle can be towed.

Abstract: In a system for controlling an automatic transmission, at the time of ultra-low temperature start with the oil temperature of −20° C. or less, control is carried out such that when the state that the actual line pressure is equal to or greater than an ultra-low set value continues for a period longer than a line-pressure low-pressure control command set time, it is determined that the line pressure is under regulation, maximizing an indicated value of the line pressure.

Abstract: Hydraulic control apparatus includes a belt-drive CVT, a pressure regulator valve (P.REG.V) regulating the oil pressure produced by an oil pressure source, a controller programmed to develop a transmission control signal, a transmission actuator driven based on the signal, and a transmission control valve actuated by the actuator. There are provided a first oil passage for supplying an oil pressure regulated by the P.REG.V, a second oil passage for supplying the oil pressure regulated to a primary pulley cylinder chamber of the CVT and draining the oil pressure therefrom, a third oil passage for draining the oil pressure within the cylinder chamber, and a fourth oil passage downstream of the P.REG.V. The third and fourth oil passages are connected to supply an oil pressure to the cylinder chamber and establish a minimum oil pressure required for clamping the belt depending on reduction of the oil pressure within the cylinder chamber.

Abstract: Hydraulic control system and method for a belt-drive continuously variable transmission (CVT). The system includes an oil pump operative to produce an oil pressure and an oil flow amount which are supplied to the CVT, a pressure regulator valve operative to regulate the oil pressure, an oil supply passage for supplying oil to the belt on a downstream side of the pressure regulator valve, means for detecting an engine operating condition and generating a signal indicative of the engine operating condition detected, and a controller programmed to calculate a CVT input torque based on the signal, calculate a required belt lubricating oil flow amount to be supplied to the belt on the basis of the signal and the CVT input torque, determine a minimum speed of the oil pump based on the required belt lubricating oil flow amount, and control the oil pump at the minimum speed.

Abstract: A belt-type CVT is comprised of a driving pulley and a driven pulley each of which has having a transmission piston chamber and a clamp piston chamber. An effective cross sectional area of the driving-side clamp piston chamber is equal to an effective cross sectional area of the driven-side clamp piston chamber. The driving-side clamp piston chamber is fluidly communicated with the driven-side clamp piston chamber through a common passage.

Abstract: A belt-type continuously variable transmission has a drive pulley (16) and a driven pulley (26) in which the pulley width between a fixed disk and a movable disk may be varied in accordance with oil pressure, a V-belt (5) which is wound around the drive pulley and driven pulley, and a clutch for controlling the transmission of torque from an engine to the drive pulley. The belt-type continuously variable transmission further has a first spring (40) for constantly urging the movable disk of the drive pulley to the fixed disk side and a second spring (41) for constantly urging the movable disk of the driven pulley to the fixed disk side.

Abstract: A method is provided for controlling an output/input speed ratio of a continuously variable transmission (CVT) plant including primary and secondary pulleys actuated by primary and secondary pressures (Pp,Ps), respectively, which generate forces to move the pulleys and adjust a corresponding belt, thereby adjusting the output/input ratio. The method includes calculating a desired force ratio for the CVT plant. Desired primary and secondary pressures (PP,PS) are then determined based, in part, upon the calculated desired force ratio, and the desired PS and PP signals are sent to the CVT plant to control operation of the CVT plant. An actual speed ratio is calculated based on measurements of input and output speed from the CVT plant.

Abstract: A continuously variable transmission (CVT) assembly includes first and second pulley pairs having a drive belt extended therebetween. A transmission case cover includes a threaded aperture. A threaded sleeve and bearing assembly is positioned on a stationary pulley member and threadedly engaged with the threaded aperture. The threaded sleeve and bearing assembly is engaged with the stationary pulley member such that rotation of the threaded sleeve and bearing assembly causes axial adjustment of the stationary pulley member. A lock feature locks the threaded sleeve and bearing assembly in the desired rotational position, thereby locking the stationary pulley member in an axially adjusted position.

Abstract: A hydraulic controller comprises a structure composed of a separator plate 70 sandwiched between first and second valve bodies 60a and 80a, in which structure, an oil passage 103 connecting a SC shift valve 92 provided upstream and a SC backup valve 94 provided downstream is provided with a choke 75. When the separator plate 70, in which a choke opening 75a is formed, is sandwiched between the first and second valve bodies, the upstream part of the oil passage 103 is in fluid communication with one end of the choke opening 75a while the downstream part of the oil passage 103 is in fluid communication with the other end of the choke opening 75a. In this arrangement, a long narrow room formed by the choke opening 75a sandwiched between the first and second valve bodies comprises the choke 75.

Abstract: A hydraulic controller (10, 10a, 10b) for a continuously variable transmission (12) is proposed. Using a pump (42), the delivery chambers (24, 26) of a first and second adjusting device (14, 16) are acted upon to alter the transmission ratio of the transmission (12). The valve (36, 36a, 36b), which can be controlled using a pressure drop created at a throttle position (50), serves to control the pressure in the delivery chamber (24). According to the invention, additional means are provided to prevent an adjustment of the transmission (12) in the “low” direction in the (N) operating state and, as necessary, in the (P) and (N) operating states.

Abstract: The invention relates to a hydraulically controllable constant speed drive, comprising an input shaft (10) provided with an input pulley (1), an output shaft (20) provided with an output pulley (2) and a drive belt (3). Each pulley (1; 2) is provided with two pulley sheaves (11, 12; 21, 22) that are mutually axially displaceable under the influence of a hydraulic pressure to be exerted in a piston-cylinder assembly (14, 15; 24, 25) associated with the pulley (1, 2) and that define a tapered groove of variable axial width wherein the drive belt (3) is accommodated. An input spring (17) is provided that realises an axial force urging the pulley sheaves (11, 12) of the input pulley (1) towards each other to prevent slip of the drive belt (3) when the hydraulic pressure is negligible.

Abstract: In a transmission unit for a hybrid vehicle, an electromagnetic clutch, a motor, and a continuously variable transmission CVT are disposed in the transmission unit and a resolver to detect a position of a rotor of the motor is disposed on an input axle to input a revolution from the electromagnetic clutch to the motor and to the CVT and is disposed on the input axle at an inner side with respect to a stator of the motor.

Abstract: A control system for a continuously variable transmission provided with a first pulley (1) having two pulley discs (5, 7), with a second pulley (2) having two pulley discs (6, 8) and with a drive belt (10) wound around said pulleys (1, 2) for transmitting torque there between, at least one disc (7) of the first pulley (1) being axially movable with respect to the other disc (5) of the pulley (1) under the influence of an axial force provided on the movable disc (7) by a line pressure (PLP) in a cylinder (11) of a piston/cylinder assembly (11, 13) associated with the the first pulley (1) and at least one disc (6) of the second pulley (2) being axially movable with respect to the other disc (8) of the pulley (2) under the influence of an axial force provided on the movable disc (8) by a second cylinder pressure (P2CP) in a cylinder (12) of a piston/cylinder assembly (12, 14) associated with the the second pulley (2).

Abstract: A shift control apparatus for controlling a continuously variable transmission device including a continuously variable transmission mechanism having rotary elements and operable to transmit a rotary motion of a drive power source of an automotive vehicle to a drive wheel of the automotive vehicle, such that a speed ratio of said mechanism is continuously variable, the shift control apparatus includes a power-transmission-state determining device for determining whether the mechanism is placed in a non-power-transmitting state, a speed-ratio determining device for determining whether the mechanism is placed in a lowest-speed position, a rotation-stop detecting device for determining whether the rotary elements are at rest, and a compulsory-speed-ratio-change implementing device for effecting a compulsory shift-down action of the mechanism toward the lowest-speed position when the mechanism is placed in the non-power-transmitting state while the mechanism is not placed in the lowest-speed position and while th

Abstract: A continuously variable transmission including two pairs of conical disks of which one disk of each pair is axially movable toward and away from the other disk and having an endless loop member in the form of a belt that passes around each pair of disks and transfers torque between the pairs of disks. The axially movable conical disk includes a contact pressure chamber to move the disk axially by the application of hydraulic pressure. The movable disk also includes an integrated torque sensor that is operative for controlling the contact pressure between the disks of a pair of disks and the endless loop member as a function of the torque.

Abstract: The invention concerns a continuously variable belt-drive transmission, especially for motor vehicles. In the pressure less state of the transmission, the axially displaceable cone pulley of the input shaft is loaded with an axial force by a spring system in a manner such that the contact pressure increases on the belt-drive mechanisms and the ratio of the transmission is reduced.

Abstract: A power transmission interruption apparatus transmits and interrupts power between an input shaft as a rotation member and a second rotation element, and between the input shaft and a fourth rotation element using a first clutch and a second clutch. In the power transmission interruption apparatus, a centrifugal hydraulic pressure canceller chamber of a first hydraulic cylinder is formed using, as a cancel plate, a cylinder tube of a second hydraulic cylinder, which causes the second clutch to be engaged. Therefore, as compared with a case where the cancel plate is separately provided, the number of components decreases, which reduces the weight and manufacturing cost. In addition, a linear dimension in the direction of the axis is shortened, which makes the configuration compact.

Abstract: A hydraulic controller comprises a first hydraulic control valve 60, which is mounted on an end face S1 of a first housing unit H1, an oil pump 50, which is mounted on the first hydraulic control valve 60, and an input shaft 1 of a transmission, which shaft is provided rotatably in a transmission housing. The oil pump 50 comprises an outer rotor 52 and an inner rotor 53 in a pump casing 51 and 54, which is mounted on the valve body of the first hydraulic control valve 60. The input shaft 1, which is inserted into the pump casing and fit into the inner rotor 53, rotates and drives the inner rotor. The oil pump 50 sucks oil from the bottom of the transmission housing and supplies it through the mounted part into the first hydraulic control valve 60.

Abstract: A transmission unit includes a transmission mechanism and a hydraulic control valve unit for controlling the transmission mechanism. The hydraulic control valve unit is disposed at a plane parallel to an axis of the transmission mechanism. A housing encloses the transmission mechanism and has a depressed portion which is overlapped with the hydraulic control unit installed to the housing. An electric oil pump is disposed on the depressed portion of the housing so that a part of the hydraulic control valve unit is overlapped with a part of the electric oil pump.

Abstract: A continuously variable transmission includes a set of pulleys mounted on respective pulley shafts (35, 36) and mounted with an endless transmission element for transmitting rotational movement from one pulley to the other, whereby the pulleys are incorporated in the transmission pre-mounted on an common support plate (22). The transmission thereby is provided with a favorable produced housing.

Abstract: The invention concerns a continuously variable transmission especially for a motor vehicle. During a zero pressure condition of the transmission, the axially slidable conically tapered disk, on the input shaft, is subjected to a spring force, by a spring arrangement, so that the pressure on the V-belt is increased and the gear ratio of the transmission is lowered to an acceptable level to prevent inadvertent damage to the transmission.

Abstract: A continuously variable transmission having a primary pulley and a secondary pulley on which a belt wound on the primary pulley is fitted. The width of the groove on the primary pulley is adjusted by the oil pressure in the primary hydraulic chamber in the primary cylinder, the width of the groove on the secondary pulley is adjusted by the oil pressure in the secondary hydraulic chamber in the secondary cylinder. The switching operation between the speed change operation in a state in which the line pressure is supplied to the secondary hydraulic chamber and the primary pressure is supplied to the primary hydraulic chamber by the oil passage switching valve, and the speed change control in a state in which the line pressure is supplied to the primary hydraulic chamber and the primary pressure is supplied to the secondary hydraulic chamber can be performed.

Abstract: An automatic transmission control apparatus includes a continuously variable transmission (CVT) which, in turn, includes a primary pulley, a secondary pulley, a belt stretched between the primary pulley and the secondary pulley. The control apparatus further includes a pinching pressure generator for generating a pinching pressure on the belt, a travel environment all detector for detecting the travel environment of a vehicle, a torque variation estimator for estimating the transmission torque variation during travel, and a pinching pressure changer for changing the pinching pressure based on the estimation. The pinching pressure is prevented from constantly increasing because the transmission torque variation during travel is estimated, and the pinching pressure for the belt is changed based on the estimation. Accordingly, the torque transmission efficiency can be increased, and the fuel efficiency can thus be improved.

Abstract: In a belt type continuously variable transmission, the apertures 55a, 56a of the drain ports of an oil pressure control valve employed for control of hydraulic devices are arranged outside of the circumferential region WB of the range of movement in which the belt can be moved in the pulley axis direction when the pulley groove width is changed during gear change operation, or outside of the circumferential region WP of the region in which the V groove face of the pulley can be arranged when the pulley groove width is changed during gear change operation.

Abstract: The device for controlling a CVT transmission which is connected with a pendulous drive, especially an internal combustion engine for a motor vehicle having front-transverse drive, has a hydromotor simultaneously used as sensor and actuator, the output signal of which is a function of the size and of the dynamics of the engine torque, the same as an electrohydraulic control unit which controls the actuating areas of the primary and secondary pulleys of the CVT via electromagnetic actuating elements and hydraulic valves. In addition to pressure-regulating valves, pressure-reducing valves and at least one emergency valve, the device has a coupling of the hydromotor with the second pressure-reducing valve via a line which coupling is used for torque modulated control of the second pressure-reducing valve in an emergency operating mode.

Abstract: A hydraulic controller (10, 10a, 10b) comprising a power part that is supplied by a high-pressure pump (42), and a control part and connecting lines is proposed. According to the invention, a low-pressure pump (64) is provided for the control part. This has an advantageous effect on leakage and fuel consumption.

Abstract: An oil-hydraulic circuit of a continuous belt variable speed-change transmission including primary and secondary variable pulleys, in which at the time when a failure occurs in a solenoid valve, the line pressure of a necessary minimum level is ensured through increasing the oil-hydraulic operating fluid supplied to a secondary pulley. On the other hand, the discharge side of a regulator valve and a primary pulley are maintained in a state of mutual communication to thereby make the speed-change ration equal to or smaller than 1. Also, when the oil pressure supplied to the secondary pulley has increased up to a prescribed, or higher than prescribed level, this oil pressure that is supplied thereto is reduced by means of a second outlet valve. As a result of this, in the oil-hydraulic circuit, even when a failure occurs in the control circuit, the safety of driving of the vehicle is reliably ensured with a simple construction of the oil-hydraulic circuit.

Abstract: A system for adjusting the tension of a continuous part of a continuously variable transmissions; which is adjustable preferably with respect to its transmission ratio, the continuously variable transmission being mounted together with a vehicle engine and at least one clutch and a vehicle engine in the drive train of the vehicle, the clutch having various operating states. The essence of the invention is the adjustment of the tension at least in dependence upon the operating state of the clutch. The adjustment of the tension of the continuous part is especially advantageous when it is undertaken in dependence upon whether an adjustment of the transmission ratio of the continuously variable transmission takes place toward higher transmission ratios or to lower transmission ratios. Furthermore, the adjustment of the tension can take place in dependence upon the activation of an ABS system, ASR system and ESP system.

Abstract: A device for hydraulically controlling a continuously variable transmission by decreasing the load exerted on an engine to improve the fuel efficiency and preventing the slipping. The device includes a belt slip detector unit 27 which forms a slip detection signal DS when a slipping state of a V-belt is detected, and a belt slip suppressing unit 25, 26, SW1 which executes a correction processing for suppressing the slipping in response to the slip detection signal. The line pressure is set to a minimum required value until the slip is detected, and the correction processing is executed for suppressing the slip only when the slip is detected.

Abstract: A system hydraulically adjusts the transmission ratio of a continuously variable transmission in a motor vehicle. The adjustment of the transmission ratio takes place by the drive of at least one valve via an electrical signal. Furthermore, in one operating state of the transmission, the transmission ratio is held essentially constant in that the electrical signal is set to a pregivable value. The valve then assumes the above-mentioned center position (blocking position). This operating state is also characterized as the ratio-hold state. The pregivable value can be changed in the normal operation of the vehicle. Component tolerances are compensated during operation of the vehicle or the transmission.

Abstract: A method is described for control of a CVT automatic transmission (1) in which a sensed main pressure (p_hd_act) and a sensed contact pressure (p_s2_act) of a secondary pulley (7) are entered as signals in an electronic transmission control (8). For diagnosis of an error in the sensing of the main pressure (p_hd_act) and/or of the contact pressure (p_s2_act) of the secondary pulley (7) their actual values or comparison variable (|p_hd_act-p_hd_nom|, |p_s2_act-p_s2_nom|) formed therefrom are compared with applicable threshold values (p_hd_min, pd_phd_regdiff, p_s2_min, pd_ps2_regdiff) associated with a range of plausible pressure values.

Abstract: A system (10), in particular an electrohydraulic system (10), for adjusting the contract pressures of a continuously variable gear, in particular a double-cone pulley belt-contact gear, which has a device for changing the gear ratio of the gear having at least one primary pressure chamber and one secondary pressure chamber is proposed. An electrically triggerable primary pressure valve (Vprim) for adjusting the pressure in the primary pressure chamber and an electrically triggerable secondary pressure valve (Vsec) for adjusting the pressure in the secondary pressure chamber are provided. The pressure (pprim) of the primary pressure chamber and the pressure (psec) of the secondary pressure chamber can be carried to the secondary pressure valve (Vsec). The object is to enable a more-accurate adjustment of the pressure (pprim) in the primary pressure chamber.

Abstract: In an emergency hydraulic control, in which in an open hydraulic circuit for supplying the various piston chambers of the secondary and primary axial adjusters, at least one throttle valve is disposed. For regulating the primary and secondary pressure, a primary and secondary valve are used, respectively. Each valve is triggered in turn via a respective electromagnetically actuated pilot control valve in the pilot control valve that opens in emergency operation; the pilot control valves are connected to the outlet of the secondary valve, among others, via orifice valves. The pressure fluid pressure in the primary piston chamber is additionally limited by a pressure limiting valve. The outlet of this pressure limiting valve is connected via a control line to the control line located between the primary pilot control valve and the primary valve.

Abstract: A transmission has a hydraulic control device (200) to pressurize actuating members arranged on a rotary shaft (280) through a fluid connection between the stationary hydraulic device and the rotary shaft. The fluid connection consists of coaxial tubular elements (220, 240) with a tubular passage channel between the inner and outer tubular elements. The tubular elements have sealed connections (221, 223, 243, 244) with the rotary shaft and the hydraulic device.

Abstract: The continuously variable belt transmission is provided with a fixed sheave and a movable sheave provided on a secondary shaft, a first hydraulic chamber that presses the movable sheave in an axial direction, a second hydraulic chamber that gives the movable sheave a pressing force acting in a direction opposite the pressing force given by the first hydraulic chamber, an oil passage connected to the second hydraulic chamber, and an oil receiver disposed along a path from the oil passage to the second hydraulic chamber. The oil receiver is attached to the secondary shaft, a bearing and a bulkhead are disposed on both sides of the oil receiver, an oil passage is provided in the secondary shaft, and a grooved portion provided in the oil receiver connects the second hydraulic chamber and the oil passage.

Abstract: A hydraulic fluid feed mechanism that feeds into a shaft (1) of a transmission having a hydraulic control device, by which the hydraulic feed mechanism can be supplied with hydraulic fluid, comprising a transmission housing (3) in which the shaft is held, and a housing cover (7) that is equipped with feed bores (8, 9), by which the hydraulic fluid is fed from the hydraulic control device into the shaft (1). It is proposed that a hydraulic fluid line (12) be positioned between the hydraulic or pneumatic control device and a feed bore (9) in the housing cover (7) that extends parallel to the shaft (1), with this hydraulic fluid line being comprised of a fitting (13) and a tube (14) which is permanently inserted into the fitting at nearly right angles, forming a pressure-tight seal.

Abstract: A pressure feed in a shaft (1) of a transmission with a hydraulic or pneumatic control device through which the pressure feed can be acted upon with the pressure medium, with a gearbox (2), in which the shaft (1) is positioned through at least one bearing (3), whereby the gearbox (2) has a bearing bore (4) in the region of the bearing (3) and whereby the bearing (3) is affixed axially in the gearbox (2) using a retaining sheet (5), with a gearbox cover (6) which covers the bearing bore (4) of the gearbox (2) and has feeding bores (7, 8) through which the pressure medium is transmitted from the hydraulic or pneumatic control device to the shaft (1). It is recommended that a pressure line (10) consisting of a tube (11) and a connection piece (12) inseparably connected pressure-tight to the tube be arranged between the hydraulic control device and a feeding bore (8) of the gearbox cover (6) arranged parallel to the shaft (1).

Abstract: A CVT-oil-pressure control apparatus has a primary cylinder provided for a primary pulley, having an oil chamber for applying an oil pressure to the primary pulley and a balance oil chamber for applying a centrifugal oil pressure to the primary pulley in a direction which is reverse of a centrifugal oil pressure generated in the oil chamber; a primary valve for adjusting a primary pressure to be applied to the oil chamber based on a line pressure applied by an oil pump; and a balance oil line that connects a drain port of the primary valve and the balance oil chamber. The oil is supplied from the primary valve to the balance oil chamber through the balance oil line.

Abstract: A hydraulic system of a CVT transmission of a motor vehicle is proposed, which has an oil pump for conveying oil from an oil sump to a variator comprising a first pulley set and a second pulley set. In each case, a valve mechanism is provided for controlling a pressure acting on the pulley set concerned. Between the valve mechanisms associated with the respective pulley sets is arranged a pressure selector valve, whose position determines which of the the valve mechanisms controls a main pressure to be delivered by the oil pump.

Abstract: An arrangement for operating a CVT transmission of a motor vehicle is proposed which comprises a hydraulic circuit supplied from a hydraulic pressure source (8) having two parallel second branches (16, 17) attached to the first branch (9) of the hydraulic circuit each for supplying pressure to a hydraulic actuator (4, 5) for respectively a cone pulley pair (2, 3) of the transmission wherein with the first branch (9) and each second branch (16, 18) an independently controllable pressure valve system (12, 13, 18, 19, 20, 21) is associated for adjusting the hydraulic pressure in the respective branch (9, 16, 17). According to the invention at least one of the pressure valve systems (18, 19, 20, 21) associated with the second branches (16, 17) has a controllable pressure-differential valve (18, 19) connected between the first branch (9) and the second branch (16, 17) concerned.